U.S. patent number 5,302,021 [Application Number 08/059,954] was granted by the patent office on 1994-04-12 for method of preventing the formation of an air pocket in a blender.
This patent grant is currently assigned to Vita-Mix Corporation. Invention is credited to John K. Barnard, Richard D. Boozer, David Jennett.
United States Patent |
5,302,021 |
Jennett , et al. |
April 12, 1994 |
**Please see images for:
( Certificate of Correction ) ** |
Method of preventing the formation of an air pocket in a
blender
Abstract
An air pocket is often formed in fluid (F) in the pitcher (14)
of a blender around the rotating mixing blade assembly (24)
thereof. The air pocket is of a cross-sectional size defined by an
air channel defining member, shown in the form of a bearing housing
(23) of the mixing blade assembly (24). After the pitcher (14) is
filled with the fluid (F), the plunger portion (12) of an accessory
(10) is positioned adjacent to and above the mixing blade assembly
(24) and maintained free of contact with the pitcher (14). The
plunger portion (12) is of a cross-sectional size approximately the
cross-sectional size of the air channel defining member and
prevents the formation of the air pocket in the fluid (F) around
the blade assembly (24).
Inventors: |
Jennett; David (Olmsted
Township, Cuyahoga County, OH), Boozer; Richard D. (Columbia
Station, OH), Barnard; John K. (Bay Village, OH) |
Assignee: |
Vita-Mix Corporation
(Cleveland, OH)
|
Family
ID: |
25334299 |
Appl.
No.: |
08/059,954 |
Filed: |
May 13, 1993 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
860892 |
Mar 31, 1992 |
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Current U.S.
Class: |
366/348; 241/30;
366/314; 366/349; 81/488 |
Current CPC
Class: |
B01F
15/00 (20130101) |
Current International
Class: |
B01F
15/00 (20060101); B01F 015/00 () |
Field of
Search: |
;366/129,130,197,205,242,244,245,247,249,314,347,348,349 ;99/646C
;15/105 ;D7/378,413,414,665,682,688 ;294/1.1 ;81/488
;241/25,30,169.2,199.12,282.1,282.2 ;100/95-97,295 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
Vita-Mix Corporation, 8615 Usher Road, Cleveland, Ohio 44138, 1
page of an instruction manual, undated..
|
Primary Examiner: Hornsby; Harvey C.
Assistant Examiner: Cooley; Charles
Attorney, Agent or Firm: Renner, Kenner, Grieve, Bobak,
Taylor & Weber
Parent Case Text
This application is a continuation of application Ser. No.
07/860,892, filed Mar. 31, 1992 now abandoned.
Claims
We claim:
1. A method of preventing the formation of an air pocket around
rotating blades positioned in a pitcher of a blender, the air
pocket being created from an air channel of a cross-sectional size
defined by a member associated with the blades, comprising the
steps of supplying a fluid into the pitcher, and positioning a
plunger, having a cross-sectional size approximating the
cross-sectional size of the member, adjacent to and above the
rotating blades while maintaining the plunger free of contact with
the pitcher thereby preventing the formation of an air pocket in
the fluid around the rotating blades.
Description
TECHNICAL FIELD
The present invention relates to an accessory for use with a
blender. More particularly, the present invention relates to a
device which can be inserted into a high speed liquid food blender
which prohibits the formation of a dead space or air pocket often
formed in such blenders around the mixing blades, which dead space
prohibits proper mixing.
BACKGROUND ART
High speed liquid food blenders most often utilize propeller-like
blades to pulverize and otherwise mix the food being processed. In
normal operation the food is circulated down to and past the blades
for processing, and as long as the circulation pattern is
consistent and uniform, efficient pulverization and mixing takes
place.
However, particularly when mixing thicker, more viscous liquids, a
channel of air is often formed extending from above the blades to
the top of the blender, much as in a whirlpool effect. As the
channel of air is drawn to the blades, an air bubble or dead air
space is eventually formed around the blades which prohibits the
food being processed from contacting the blades and thereby
rendering the blades ineffective to mix the food. Presently, this
can only be corrected by manually stirring the food to disperse the
air pocket away from the blades. However, the air pocket will
usually readily reappear thus making the blending process not only
inefficient but also bothersome to the user.
DISCLOSURE OF THE INVENTION
It is thus a primary object of the present invention to provide a
plunger accessory for a blender which prevents the formation of a
dead air space around the mixing blades of the blender.
It is another object of the present invention to provide a plunger
accessory, as above, which cannot interfere with the blades of the
blender while eliminating the dead air space.
It is a further object of the present invention to provide a
plunger accessory, as above, which can be utilized to prevent the
dead air space without the constant attention of the user.
It is an additional object of the present invention to provide a
plunger accessory, as above, which can also be used to stir the
food material being processed.
These and other objects of the present invention, as well as the
advantages thereof over existing prior art forms, which will become
apparent from the description to follow, are accomplished by the
improvements hereinafter described and claimed.
In general, the blender accessory according to the present
invention includes a plunger portion having a stop member
positioned near the top thereof. The plunger is received through an
opening in the cover of a blender and into the blender pitcher
therebelow. The stop member rests on the cover and the plunger is
of a predetermined length so that the bottom thereof is just above
a mixing blade assembly positioned near the bottom of the pitcher.
The blade assembly has an air channel defining member, such as a
bearing housing, and the size of the plunger approximates that of
the bearing housing to close off the air channel and thereby
prevent the formation of an air pocket which would otherwise be
formed as the blade assembly mixes the fluid food in the
pitcher.
A preferred exemplary plunger accessory for a blender incorporating
the concepts of the present invention is shown by way of example in
the accompanying drawings without attempting to show all the
various forms and modifications in which the invention might be
embodied, the invention being measured by the appended claims and
not by the details of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a plunger accessory for a blender
constructed in accordance with the concepts of the present
invention.
FIG. 2 is a sectional view of a portion of a blender showing the
plunger accessory in use therein.
REFERRED EMBODIMENT FOR CARRYING OUT THE INVENTION
A plunger accessory for a blender is indicated generally by the
numeral 10 and is shown as including a generally cylindrical handle
portion 11, and a generally cylindrical plunger portion 12
separated by an enlarged generally circular shoulder or stop member
13. As will hereinafter become evident, plunger portion 12 need not
be cylindrical but rather could take on any suitable geometric
shape. Moreover, while stop member 13 is shown as being a generally
circular disk, it could be of any other configuration which
performs the stop function, to be hereinafter described, the disk
shape being preferred because that shape enables stop member 13 to
perform the additional function of closing the top of the
blender.
Plunger 10 can be formed of any suitable rigid material, such as
plastic, and handle 11 and plunger portion 12 may be tapered, as
shown, to facilitate the molding process. Handle 11 may be of any
desired length convenient for facile gripping by the user; however,
as will be hereinafter described, the length of plunger portion 12
should be such that when positioned in a blender, such as shown in
FIG. 2, the bottom thereof will not interfere with the blender
blades.
With reference to FIG. 2, some of the components of a typical
blender are shown therein which include a pitcher portion generally
indicated by the numeral 14 which holds the fluid F to be mixed,
and a cover portion generally indicated by the numeral 15. Pitcher
14 can be of any conventional configuration and is shown as having
tapered cylindrical side walls 16 and an upper shoulder 17
extending outwardly to form an enlarged upper lip 18. Similarly,
cover 15 can be of any conventional configuration and is shown as
including a top portion 19 having a skirt 20 extending downwardly
therefrom. The bottom of skirt 20 rests on the upper shoulder 17 of
pitcher 14 to close the top of pitcher 14. Top portion 19 of cover
15 is provided with a central aperture 21 which, if desired, may be
closed by a dome plug (not shown) for certain applications of the
blender.
A motor driven shaft 22 extends upwardly through a bearing housing
23 into the bottom of pitcher 14 and carries a mixing blade
assembly generally indicated by the numeral 24. Blade assembly 24
can be of any conventional configuration with the blade assembly 24
shown including four circumferentially spaced propeller-like
blades, only two being shown as numerals 25 and 26. At least some
of the blades may be provided with upturned blade members, such as
member 27 shown in FIG. 2.
In operation, with pitcher 14 filled with fluid material F to be
processed and with cover 15 in place, the motor (not shown) is
actuated to rotate mixing blades 24. As such, the fluid is drawn
between the propeller-like blades and circulates back up to the
upper surface. In the absence of the plunger accessory 10, and in
particular when processing viscous fluids, such action may tend to
form an air channel extending from the blades to the top of the
fluid much like a whirlpool. Eventually, an air pocket will form
around the blades which renders the blades ineffective for a total
blending of the fluid. The air channel which forms above the blades
is usually of a size dictated by the air channel forming member of
the blade assembly. For the particular blade assembly shown,
bearing housing 23 dictates the size of the air channel which is
thus of a diameter of approximately the size of bearing housing 23.
For other types of mixing blades, such as ones having a central hub
from which the blades extend, the size of the air channel is
dictated by that hub and is thus usually of a diameter of the
central hub.
Plunger accessory 10 prevents the deleterious formation of such an
air channel and thereby prohibits the ultimate formation of an air
pocket around the blades. As shown in FIG. 2, plunger portion 12 of
accessory 10 is inserted through cover aperture 21 with stop disk
13 resting on cover top portion 19. This not only closes cover 15
but also limits the downward extent of plunger portion 12. As such,
plunger portion 12 is designed to be of a length so as to be
positioned just above the mixing blade assembly 24 when positioned
in the blender. Thus, the length of plunger portion 12 is dictated
by the size of the blender being employed.
The diameter of at least the bottom of plunger portion 12 is also
important to carrying out the advantages of the present invention.
Basically, it is preferably of a size approximately equal to the
air channel defining parameter of the blender. Thus, for the
blender shown in FIG. 2, it is designed to be of a size
approximately equal to the size of bearing housing 23. In actual
practice, it has been found that if the size of the bottom of
plunger portion 12 is .+-.25% of the size of the air channel
defining member, neither the channel nor the eventual air pocket
will be able to be formed. Thus, as shown in FIG. 2, when the
blender is operating the fluid is properly circulated along the
side of plunger 12, through the blades, around the outer tips of
the blades, and back to the top as shown by the arrows. Thus, the
potential for forming the deleterious air pocket around and above
the mixing blade is eliminated.
Plunger accessory 10 can also be utilized by the user as a stirring
mechanism. If additional stirring is desired, one need only grasp
handle portion 11 and oscillate plunger accessory 10 to move
plunger portion 12 from side to side within pitcher 14 to create
the additional stirring desired.
It should thus be appreciated that a plunger accessory constructed
and utilized as described herein accomplishes the objects of the
present invention and otherwise substantially improves the fluid
food blending and processing art.
* * * * *